2.2.2

Question 1

Ionic compounds properties GIS

Answer 1

High melting & boiling points

Strong electrostatic forces - large amounts of energy needed to break

Electrostatic forces - hold opposite charged ions together , why ionic compounds have high mp & bp

Question 2

Electrical conductivity GIS

Answer 2

Ions in fixed position, cannot move

Non-conductor of electricity

Question 3

Electrical conductivity when melted or dissolved in water GIS

Answer 3

Solid lattice breaks down & ions free to move

Ionic compound now a conductor of electricity

Question 4

GIS solubility

Answer 4

Dissolves in polar solvents (e.g. water)

Polar water molecules break down lattice by surrounding each ion to form a solution

Question 5

Giant ionic lattice

Answer 5

Solid ionic compound exist as giant ionic lattices

Strong electrostatic attraction between opp charged ions result in a high melting point

Question 6

Polyatomic ions

Answer 6

E.g. OH-, SO42-

Have covalent bonds within polyatomic ons

Form ionic bonds with other ions

Question 7

Ionic bonding strongest

Answer 7

When one/both ions have a high charge and are small

MgO > NaCl as Mg=2+, O=2-

Question 8

2 non-metals

Answer 8

Covalent bonding

Question 9

Metal + non-metal

Answer 9

Ionic

Question 10

Noble gases

Answer 10

Stable electron configuration

Full outer shell so, very stable

Question 11

Covalent bonding

Answer 11

Strong electrostatic attraction between a shared pair of electrons and the nuclei of the bonded atoms

Question 12

Double bond

Triple bond

Answer 12

2 shared pairs of electrons

3 shared pairs of electrons

Question 13

Dative covalent bonding (co-ordinate bonding)

Answer 13

One of the atoms supplies both the shared electrons for the covalent bond

E.g. ammonium ion, NH4+
Nitrogen atoms donates a pair of electrons to a proton (H+ ion)

Question 14

Average bond enthalpy

Answer 14

Energy needed to break one mole of a particular bond

Always exothermic

Larger the value of the bond enthalpy, the stronger the covalent bond

Question 15

Ions

Answer 15

An atom may become charged when the number of electrons is altered (loss or gain of electrons)

This charged atom is called an ion

Question 16

Metals

Answer 16

Lose electrons > cations (pos charged ions)

Question 17

Non-metals

Answer 17

Gain electrons > anions (neg charged ions)

Question 18

Ionic bonding

Answer 18

Occurs due to strong electrostatic forces of attraction between pos and neg charged ions

Question 19

Monatomic

Answer 19

Existing as a single atom (group 0)

Question 20

Octet rule

Answer 20

Full outer shell typically with 8 electrons

Question 21

Outer shell

Answer 21

2n2 n - principle quantum number

Question 22

For dative covalent bonds to form

Answer 22

Acceptor molecule must be electron deficient (available orbitals for the electron to occupy)